Buknell b



Patented July 17, 1928.

UNITED STATES PATENT OFFICE.

BURNELL R. TUNISON, F ELIZABETH, NElV JERSEY.

ORE CONCENTRATION.

NoDrawing. Application filed February This invention consists ofimprovements in processes ofore COUCQlll'lzltlOl'l, andhas particularreference to ore concentration by flotation- In these processes thepowdered ore is usually mixed with water, such mixture being termed thepulp, and to this pulp added the flotation agent, consisting of an oilor oils, or a frothing agent or agents, or both, and thepulp is'thensubjected to agil0 tation and aeration; for example, supraaeration byair introduced from above by beating it into the pulp, or by subaerationby air introduced from below through a po' rous medium or otherwise. Aswell known in the art, the result of this aeration is that the airbubbles coursing through the pulp gather up the metalliferous particlesand carry them to the surface where they form a froth. This froth may bereadily floated over a lip or dam and will thus carry the metalliferousparticles away from the body of the liquid. In these processes a mineralacid, such as sulfuric acid, is in some instances used in addition tothe frothing agent, and in other instances an alkali is used in additionto the frothing agent, and these additional substances, acid oralkaline, act in some manner not clearly understood to modify theproperties of the liquid or ore and to assist the flotation of thenietalliferous mineral and to retard or prevent the flotation of thegangue.

This invention relates specifically to the process of ore concentrationby the use of oils containing sulfur compounds, many of them quitecomplex in their constitution, which oils have unusual and valuablecoating, flocculating, and in many instances frothing and sulfldizingproperties. These oils may be obtained from petroleum and its products,shale oil and its products, coal tar and its products, still gases andresidues, oxidized oils, wood oils etc., by treating them substantiallyas described in my co-pending application Serial No. 691,811 entitledFlotation agents and process of producing same, filed on February 9,1924.

As disclosed in my said co-pending application the flotation agent maybe produced from the above named materials, by washing the material withalkali, for instance, with a solution of caustic soda, with agitationand allowing the mixture to settle. The mixture will become stratifiedinto an alkali layer and an oil layer. The alkali layer, however,contains some oil, and particularly oil con- 9, 1924. Serial No.691,810.

twining sulfur compounds. This oil is then extracted from the alkalilayer either by adding an acid, for instance, sulfuric acid, toneutralize the removed. alkali layer, which will cause the oil toseparate out that it can be removed physically, or the oil may be takenup with a solvent, for instance, benzol, and ren'iovcd therewith, andrecovered from the solvent by distilling the solvent away. Preferably,thereafter the oil is washed. The alkali above referred to may he a18-24? gravity caustic soda solution, and theacid may be sulfuric acidof 90-98% strength, although my process is not limited to these specificelements or strengths, and may be carried out by the use of an alkaliother than caustic soda, and the alkali treatment may be made eitherpreceding or subsequent to an acid treatment, usually sulfuric acid, ascarried out in petroleum refinin An exceptionally good flotation agentis produced by treating apetroleum distillate, for instance, naphtha, inthe above manner.

Several types of ores may be very successfully concentrated by flotationby means of this invention. Sulfide ores, for example, chalcocitc,chalcopyritc, galena, and sphalerite, and the like with the siliceousganguc may be treated by flotation, and the separation of themetalliferous products from the ganguc is much more complete by means ofthis process. Oxidized ores such as malachite, azuritc, and cerussitehave been successfully treated by means of this process. In cases wheresulfidizing agents are at present used in practice, the use of thisprocess permits a marked reduction in the quantity of sulfidizing agentnecessary. In the use of these sulfidized oils, the quantity necessarywill vary materially with the type and quality of the ore to be treated.Sulfide ores usually require from one-half pound, orless, to two poundsper ton of ore treated. hen an ore difficult of flotation is to be used.such as mixed oxidized and sulfide ma terial, or some of the low gradeporphyries, a quantity of oil up to four or five pounds per ton may benecessary. 111 cases where a sulfidizing agent such as sodium sulfide isused in practice, the use of this invention will. make possible aconsiderable reduction in the quantity of sulfldizing agent necessary.

In using this invention, the flotation materials may be added to the orealone or in admixture with other agents promoting the flotation, in anysuitable n'ianner, so that they Will be thoroughly and uniformlydistributed throughout the ore pulp. In applying the materials they maybe introduced into the tube mill in which the ore is being ground orthey may be otherwiseintroduced into the ore pulp in any suitable Way.

What I claim is 1. A process of efliecting the concentration of mineralsby froth flotation, which comprises subjecting to froth flotation amineral pulp in the presence of the extracted oily sulturous componentof a sulfurous petroleum oil, said extracted component being soluble incaustic and insoluble in Water.

,2. A process of effecting the concentration of minerals by frothflotation, which com prises subjecting to froth flotation a mineral pulpin the presence of a sulfurous oil extracted from an alkali solution ofconstituents of a distillate of a sulfurous petroleum oil.

3. A process of effecting the concentration of minerals by frothflotation, which oomprises subjecting to froth flotation a mineral pulpin the presence of a sulfurous oil extracted as such from the alkalilayer formed pulp in the presence of a sulfurous oil ex-' tracted assuch from the alkali layer formed upon mixing caustic soda with acllstillate of a sulturous petroleum Oll.

This specification signed this 12th day of May, 1925. I I 'BURNELE R.'TUNISON.

